IP Library › Granted Patent US 12,378,128
Granted Patent B2
US 12,378,128 · App. 17/291,565 · Granted Aug 5, 2025

Method for producing aerogels and aerogels obtained using said method

Inventors: Damian Hintemann (Stadtlohn, DE); Andreas Kilzer (Witten, DE); Nils Mölders (Mülheim an der Ruhr, DE); Manfred Renner (Essen, DE); Andreas Sengespeick (Minden, DE); Eckhard Weidner (Bochum, DE); Oliver Weishaupt (Gladbeck, DE)
Assignee: Fraunhofer Gesellschaft zur Förderung der angewandten Forschung e.V.
C01B33/1585B01J13/0091C01B33/1546C01B33/159C01P2004/32C01P2004/61C01P2006/32
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Quick Facts
Patent No.
US 12,378,128
App. No.
17/291,565
Granted
Aug 5, 2025
Kind
B2
Abstract

The invention relates to a method for producing an aerogel under increased pressure, to the aerogel obtained using said method and to their use.

Claims (15)

1. A method for producing a silica aerogel, comprising:

(a) introducing droplets of a sol into an apparatus subjected to a pressure of more than 30 bar to form a particulate lyogel, wherein:

the sol has a pH greater than 7 and is a solution or dispersion of a precursor in a solvent or dispersant,

the apparatus contains compressed carbon dioxide and formation of the particulate lyogel is initiated by a pH shift of the sol due to the compressed carbon dioxide, and

the sol has not been pre-gelled or partially gelled by an acid or base before being introduced into the apparatus; and

(b) following step (a), performing a solvent exchange of the lyogel.

2. The method according to claim 1 , wherein:

the pressure in step (a) is more than 40 bar; and/or

step (a) is carried out at a temperature above 50° C.

3. The method according to claim 1 , further comprising converting the lyogel into an aerogel by removing a solvent or dispersant of the solvent exchange of step (b) from the lyogel at a pressure of more than 50 bar.

4. The method according to claim 1 , wherein the precursor is selected from silicic acids, colloidal silicic acid, colloidal silica, silanes, silica sols, tetraalkoxysilanes, siloxanes and mixtures thereof.

5. The method according to claim 1 , wherein the sol comprises a hydrophobing silanizing agent.

6. The method according to claim 1 , wherein the solvent exchange occurs by contacting the lyogel with an organic solvent.

7. The method according to claim 6 , wherein the organic solvent is brought into contact with the lyogel together with a hydrophobing agent.

8. The method according to claim 7 , further comprising, subsequent to contact with the organic solvent and hydrophobing agent, converting the lyogel into an aerogel.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 2, 2021
From: HINTEMANN, DAMIAN; KILZER, ANDREAS; MÖLDERS, NILS; RENNER, MANFRED; SENGESPEICK, ANDREAS; WEIDNER, ECKHARD; WEISHAUPT, OLIVER
To: FRAUNHOFER GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Reel/Frame 056413/0182 →
Priority Claims (1)
DE 10 2018 128 410.1 · Nov 13, 2018 · national
Continuity (1)
Related Publication 20220009786A1 · Jan 13, 2022
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